How to prepare for thunderstorm asthma

Thunderstorm asthma can be deadly, so understanding the risks, triggers and signs is crucial.

In 2016, Melbourne experienced the world’s largest epidemic thunderstorm asthma event, which resulted in thousands presenting to hospitals with respiratory-related symptoms.

Tragically, it also resulted in 10 deaths.

The incident was unprecedented, with a perfect storm of factors coming together to cause such a mass asthma event.

It prompted an important warning to be prepared, particularly for those most at risk.

Here’s what you need to know about thunderstorm asthma.

What is thunderstorm asthma?

“(Thunderstorm asthma is) when people experience severe asthma symptoms induced by high grass pollen levels in combination with thunderstorm weather activity,” says University of Technology Sydney School of Life Sciences Professor Alfredo Huete, a member of the Victorian Thunderstorm Asthma Pollen Surveillance Network.

“When certain types of thunderstorms react with high grass pollen conditions in the surrounding rural environment, it can result in a fine mixture of pollen fragments in which thunderstorm wind gusts blow the toxic pollen mixture on to populated areas and a large number of people experience sudden breathing difficulties,” he says.

Thunderstorm asthma events are uncommon but generally occur between October and December, says leading researcher Professor Frank Thien, director of Respiratory Medicine at Melbourne’s Eastern Health.

Most of the events recorded in Australia have happened in Victoria, particularly in Melbourne, which is thought to be due to the high concentration of ryegrass in the state.

What causes thunderstorm asthma?

A thunderstorm can sometimes provide the ideal conditions to trigger the release of the fine starch particles within a pollen grain into the air, which can cause an asthma attack, says Prof Thien.

“(Those who are allergic to grass pollen) can inhale the fine particles down into airway, which can cause spasms of the airways,” he says.

Who is most at risk of thunderstorm asthma?

Melbourne Allergy Asthma Immunology Consultants allergist Dr Celia Zubrinich says those most at risk of experiencing thunderstorm asthma are:

  • People with an allergy to grass pollen
  • People with asthma
  • People with seasonal hay fever
  • People with undiagnosed asthma (these are people who may have experienced the symptoms of asthma such as wheezing or breathlessness but have not been formally diagnosed)

How to prevent thunderstorm asthma

Dr Zubrinich says if there is a threat of a thunderstorm asthma event and you are at risk, “it’s sensible just at that time, to stay inside and shut the windows and doors”.

Also be sure to check pollen counts and weather forecasts, which can be done through the Bureau of Meteorology and the Australian Pollen Allergen Partnership websites or the Air Rater app.

If you’re in Melbourne, download the Melbourne Pollen Count app, which provides a forecast of potential thunderstorm asthma events.

Depending on your potential risk of experiencing thunderstorm asthma, Dr Zubrinich suggests taking the following course of action:

  • If you have asthma “you should have it reviewed and have a plan. And for most people that includes being on some form of preventive therapy”.
  • If you experience hay fever and have experienced symptoms of asthma but are “not on regular therapy, you should at the very least have access to an asthma reliever in springtime and have that with you always”.
  • If you experience hay fever but have never experienced asthma symptoms then it’s important to know the signs of asthma, and how those differ to regular hay fever symptoms.
  • Even if you don’t experience any of the above, Dr Zubrinich says it’s still a good idea to familiarise yourself with asthma first aid, in case of an emergency.
  • If you are experiencing asthma symptoms but a reliever is not helping, call an ambulance immediately to seek further help.

Written by Tania Gomez.